Hand brake



J. F. (DCONNR AND BRAKE Filed Deo. 14D 19,22

lvweizff @im ,m @wwf gy Patented Sept. 14, 1926.

UNITE STATES PTENT ,FFME

Jenn F. oconnon, or eriioneo, vr-Lnrivois, nssrenon, BY Masini nssienmnnrs, 'ro

W. Minna, ino., n oonronaron HAND.

Application lled December This invention relates to improvements iIl hand brakes. y

An object of my invention is to provide, in a hand brake for railway and other cars,

means :tor quickly taking up the slack in the brake chain and automatically increasing the leverage ratio pull on the brake chain during the linal application ot the braking pressure. A further object ot my invention is to provide, in a device ot this type, automatically operable means tor adjusting the brake mechanism to compensate for excessive slack in the brake chain.

A more specific object oi the invention is to provide a hand brake of the vertical stall type with chain-winding means comprising a pair of normally simultaneously rotated drums having dill'erent peripheral winding speeds and each drum receiving one end of the chain Wound thereon and means automatically operated upon the slack having been taken'up for stopping` the operation of the Awinding drum havingthe greater peripheral speed While continuing the operation of the other winding drum, thereby increasing` the effective leverage :ratio pull on the brake chain, together with means for automatically compensating for all increase in the slack of the brake chain due to wear of the brake shoe 'faces and other partsV oit the brake rigging, thus keeping substantially constant the number of turns of `the brake stall to apply the brakes. j

Other objects of the invention will more clearly appear from the description and claims hereinafter following.

ln the drawing forming a part of this specilication, Figure l is a side elevation of a hand `brake showing my improvements in connection therewith. Fig. 2 is a horizontal sectional view taken substantially `on the line 2-2 of Fig. 1. Fig. 3 isa bottom plan view of a clutch cap used in my improved hand brake. Fig. 4c is a horizontal sectional view taken substantially on rthe lined-4I of Fig. 1. And VFig. 5 is ahorizontalsectional view taken substantially on the line 5 5 of Fig. 1. j y

ln said drawing, l0 denotes the end wall of Ya car, to which is attached ley any suitable means such as rivets 11 the horizontal angle 'beam 12 forming the top ot the built up end sill indicated generally yby A. V 'lhe channel beam 13 vforming the side wall ci' the end sill .A is suitaby ,secured to tllie'nuter BRAKE.

14, 1922.; Serial N0. 606,926.

edge ot the beam 12, by means of rivets or any other suitabe means passing through the angularly projecting flange 15 rof the beam 13 and the end of the bracket 12. i A

stirrup 16 comprising a horizontally extending bottom plate 1.7 and lvertically extend sidewalls 18 is suitably attached to the bottom of the end sill A. A horizontal plate 19 arranged between the walls 18 is attached to the inwardly projecting flange 2O at the lower edge ,ot the plate 13 by any suitable means such as rivets 21. i

A vertically extending brake stall:z 22 is shown, the same havinga Vhand wheel 23 rigidly secured to its upper end and a relatively small gear 241 lixed to its lower end to rotate in unison therewith. `of the brake statt 22 extends outwardly beyond the gearv 24 and is reducedas shown at y25, said reduced portion 25 being jour# The lower ,end`

naled in an opening 26in the `plate 17-,of the stirrup. The statt 22 has loosely rotatably mounted thereon, a sleeve 27, the latter passing through the beam 12 and plate 19, and journaled in .openings 28 and 2,9 in the beam 12 and plate l19,*respectively.

Achain-winding drum `30 is rotatably mountedbetween 4the plate 19 and bottom plate 17 of the stirrup having its upper .end journaled in an opening 31 in and its lower reduced and 32 journaled in an opening 33 in the bottoml plate 17.

. Fixed to the drum `3() is a relativelylarge gear 34 meshing with the gear 2l on the stati v22 whereby rotation of the stati in the direction of the .arrows as indicated in F ig. 5 will cause rotation of thev Lgear 341 andthe drum 30 in a direction reversel-y thereto as indicated by the arrow uassociated with these latter parts, as shown in Fig. 5. The stall 22 is formed with .a squared portion 35 .adapted to .slidingly but non-rotatably receive the collar '36. The latter `is provided with ratchet teeth 37 on :its .periphery and clutch teeth 38 on its lower ytace, saidclutch teeth 38 coacting with "clutch teeth 89 tormedon the enlarged upper end l0 of the sleeve 27. The' periphery oit the enlarged ende() is provided'with ratchet teeth 41 corresponding withv `.the ratchet teeth 37 of the .sliding collar `36. i

Accidental rotation' of ythe collar 36 and the plate 'the sleeve A27 in acountermlockwise or chain being taken up.

co-act respectively with the teeth 37 on the collar 36 and the teeth 41 on the sleeve 27 The pawls 42 and 43 are suitably pivoted on the bracket 12 by a bolt 44 and are provided with operating levers 45 and 4G respectively, Jfor disengaging the same from the respective ratchet teeth 37 and 41. The pivoted pawl 42 is so mounted that it may have independent movement relative to the pawl 43 so that the paw 43 may remain in engagement with the ratchet teeth 41 to prevent retrograde movement ot the sleeve 27 while the pawl 42 has a ratcheting action over the teeth 37 ot the collar 36.

rlhe sleeve 27, as shown in Fig. 1, has its lower end extending beyond the plate 19 and rests upon the gear 24, thus providing a chain winding drum portion 47. The chain winding drum portion 47 is provided with a laterally projecting lug 48 adapted to serve as an anchorage for the brake chain. The teeth 39 on the enlargement 40 of the sleeve 27 which co-act with the teeth 38 on the collar 36 are so designed that their inclination will offer sufficient resistance to prevent slippage of the parts during the time that the slack in the brake chain is The resistance between the teeth 38 and 39 is insuiiicient, however, to prevent slippage after a predetermined resistance is encountered inthe tightening of the chain.

Rotatably journaled and slidably mounted upon the sleeve 27 is a hollow stop cap 49 provided with inwardly projecting oppositely located lugs 50, adapted to co-act with oppositely located outwardly projecting lugs 51 on the sleeve 27. The lower edge of the stop cap 49 is provided with a series ot ratchet teeth 52, co-acting with an annular set ot ratchet teeth 53, formed integral with the plate 19. The ratchet teeth 52 and 53 are so arranged that the stop cap 49 is adapted to rotate in a clockwise direction, but is positively prevented from rotation in a counter-clockwise direction.

The brake chain 54 has one end secured to the anchorage 48 on the winding drum 47 and extends over a grooved pulley 55 journaled in the end of the brake rod 56 and has its opposite end secured tothe brake drum 30 by means of an anchoring bolt 57.

In the operation ot my improved brake mechanism, the hand wheel 23 is turned in a clockwise direction to tighten the brakes. During the normal operation of the device, upon rotation ot` the hand wheel in said clockwise direction, the chain winding drums 30 and 47 will be simultaneously rotated but in opposite directions, as indicated by the arrows .in Fig. 5, thus winding the opposite ends of the chain 54 thereon and eltecting a very rapid movement of the end ot the brake rod 56 toward the drums, with the result that the slack is quickly taken up. The simultaneous rotation ot the drums 30 and 47 is produced as follows: As the stati 22 is being rotated in a clockwise direction, the vdrum 30 driven by the inter-meshing gears 24 and 34 will be rotated in the opposite direction` as indicated in Fig. 5 and the clutch collar 36 being mounted to rotate with the stall 22 will rotate the sleeve 27 by its engagement with the teeth 39 of the enlargement 40, thus causing rotation ot the sleeve 27 in unison with the stad 22 and etlecting the winding of the chain 54 upon the drum 47, the latter being rotated in the direction indicated by the ar` row in Fig. 5.

The inter-engaging teeth 38 and 39 are so designed that their inclination will otter sutlicient resistance to prevent slippage therebetween during the time that the slack is being taken up by the chain being wound upon the drum 47, but this resistance will be overcome and the teeth 38 and 39 will slip or ratchet over each other when a greater and predetermined resistance is encountered,

such as when the brake shoes are iirst i brought against the car wheels. y

The simultaneous winding operation ot the two drums 30 and 47 continues until the predetermined resistance has been encountered, whereupon the gripping action of the teeth 38 and 39 is overcome, thus allowing the sleeve 27 to remain stationary while the rotation of the stall is continued until the brakes have been completely set. Retrograde movement of the sleeve and the stati' is independently prevented by the separate locking pawls in engagement with the ratchet teeth v37 and 41 respectively. During this independent movement ot the drum 30, the eitective leverage ratio ot the pull on the brake chain is obviously greatly in creased due to the tact that the chain is being wound only on the drum 30 which is oi smaller diameter than the drum 47 and which is more slowly rot-ated than the drum l 47, due to the reduction gears 24 and In releasing the brake mechanism, as the chain is unwound, the drums 30 and 47 will be simultaneously rotated in directions op posite to those indicated by the` arrows in Fig. 5, and the clutch teeth 38 and 39, being in engagement, the sleeve 27 and the statt' 22 will rotate in unison in a counter-clock-- wise direction until the lugs' 51 on the sleeve 27 come into contact with the lugs 50 on the collar 49, whereupon the rotation of the sleeve 27 will be positively stopped, movement of the collar in a counter-clockwise direction being positively prevented by the formation ot the teeth 52 thereon and fixed teeth 53. The rotation of sleeve 27 and the rotary drinn 47 is thus postively limited, and as a result the amount ot ro# tation ot the drum 47 in taking up the slack will be kept substantially constant. Under Lteve normal conditions, when the drum 47 is thus brought to a stop, the chain Will be completely univound from the drum 30and the latter will also come to rest, but additional rotary movement of the drum 30 is per.- mitted in case the chain is not completely unwo'nnd therefi'jom, by the teeth 3S slipping over the teeth 39 of the clutch. n

ln applying; the brakes under normal con-p ditions, the slack in the chain Will be taken up durinv the time that the sleeve is rotated in a clockwise direction, from the position in which the lugs 5l are stopped against the lugs 50 on the collar, to a position Where the ings 5l engage the opposite lugs 50, which involves slightly lessthan a half rotation, this amount of movement being' sufficient in that the sleeves are simultaneously rotated during' that time and the chain ends simultaneously ivo-,und thereon to properly take up the normal amount of slack. its the brake shoe faces and the other parts of the brake rigging become ivorn, the slack in the chain Will increase, thus requiring a greater rotation of the sleeve 27 in taking up the slack. This is taken care of by the adinstable stop cap 49. Upon any slight additional rotation of the sleeve in a clockwise direction, due to a slight increase in the slack of the brake chain over what is normally required, the lugs 5l. on the sleeve being in engagement ivith the lugs 50 on the collar, Will tend to move the latter in a clockwise direction, also, thus causing' the teeth 52 on the collar to ratchet over the teeth 53 until the excessive sla-ck has been taken up, whereupon the sleeve 27 having become stationary due to the release 'of the teeth 38 and 29 as hereinbefore described, the teeth 52 on the collar ivill re-engage With the teeth 53 with the collar in slightly advanced position. lt will thus be se'en that all the excessive slack in the brake chain is automatically compensated for as it occurs and that the rotation of the sleeve 27, in taking up the slack, remains practically constant.

W' hen it becomes necessary to replace the brake shoes, the ratchet collar is disengaged from the ratchet by engaging a proper tool Within the opposite openings 58 formed in he collar and manually raising the collar, whereupon, the drums 30 and 47 are free to rotate so that the chain may be entirely univound and the replacement of the shoes easily made. After the shoes have been replaced, rotation of the brake stal 22 in a clockwise direction Will cause the chain to be rewound upon the drums 30 and 47. During this operation, the sleeve 27 will be rotated relatively to the stop cap 49 until the lugs 51 engage the lugs 50, whereupon the stop cap vvill be rotated With the sleeve, the teeth 52 ratcheting over the teeth 53. This operation Will continue until the slack of the chain is completely taken up, whereupon thev teeth 38 and 39 on the collar 36' and the sleeve 27 respectively, will disengage, and rotation of the sleeve vvill be stopped., with the teeth of the stop cap reengaged with the fixed teeth o8 to prevent rotation of the cap in a counter-clockwise direction.

l have herein shown and described Wha-t l ncrv consider the preferred manner of carrying out the invention, but the same is merely illustrative and l contemplate all changes and modilications that come `Within thescope of the claims appended hereto.

'l claim: i

l. ln a hand brake; the combination with a rotatable chain Winding drum; of means for rotating,v said drum; 'and means comprising a stop device movable With said drum until a predetermined kresistance is reached, such stop device being adjustably secured in such position, and arranged to vpermit limited reverse movement of said drum.-

2. In a hand brake;v the combination `with a rotary brake drum; of means for rotating said drum in reverse directions to Wind and unwind the brake chain; and means for limiting' rotation of said drum in one direction comprising, a pair of interengaging` relatively adjustable clutch elements, one of said elements having' a lost motion connection. with said drum and thegother clutch element being iixedly held against rotation, said clutch elements beingl normally operative to prevent rotation thereof in a counter-clockwise direction, but permitting relative `rotation thereof in the opposite direction upon the lost motion being,l taken up by rotation of said rotating means in a chain Winding' direction to compensate for increased slack in the brake chain, thereby allowing;` relative automatic adjustment of said clutch elements.

3. ln a hand brake; the combination With a rotary brake drum; of mea-ns for rotating' said `drinn in reverse directions, to Wind and unwind the brake chain; and means for limiting the rotation of said drum in one direction, said means including` a movable element havinga lost motion connection with said drum rotating means, and a fixed stop element, said first and second named elements having co-acting means thereon permitting` rotation of said first named element in a chain Winding direction and positively preventing; rotation of the latter in an unvvinding direction.

4. In a hand brake; the combination With a rotary brake drum; of means for rotating said drum; a toothed clutch collar rotatably journaled on said means, said collar and ro-4 tary means having inter-engaging,` `lugs thereon for limiting` the relative rotation thereof; and a fixed stop element having clutch teeth thereon co-actino; with the teeth of said collar to positively prevent rotation o1c said drum'in one direction and permitm till itl() llO ting rotation of said collar in the opposite direction.

5. in a hand brake; the combination with a vertical brake statt; of a chain winding drum rotatably journaled thereon; a sleeve formed integral with said drum and surrounding said steli; a pair ot spaced lugs radially projecting` from said sleeve; a ratchet wheel formed integral with said sleeve? said ratchet wheel having clutch teeth thereon; a ratchet wheel slidably mounted upon said staff t'or rotation in unison therewith, said ratchet wheel having clutch teeth co-acting with the clutfxh teeth ol the rst named ratchet wheel; a pair ot locking pawls coaoting with said ratchet wheels; a collar rotatably mounted upon said sleeve, said collar having` clutch teeth thereon; a

air ot spaced lugs on said collar co-acting with the lugs on said Sleeve; a iixed member having clutch teeth co-acting with the teeth ot said collar; a second rotary drinn; and power transmitting gearing between. said sta-tf and said second named drum.

6. In a hand brake; the combination with a brake stati1 ot means tor winding the chain, said means including a pair ot drums ot different diameters; means operatively connecting said drums to the brake statt; an adjustable stop; and a lost motion connection between said stop and one oit said drums. i

7. in a hand brake; the combination with a brake staff rotatable in reverse directions to wind and unwind the brake chain; chain winding means rotatably journaled upon said statt; locking means directly engageable with said chain winding means to prevent winding thereof; a second chain winding means positively driven by said stan; a relcasable clutch connection between said statt and first named chain winding means automatically operable independent of said locking means; and means tor limiting the rotation ot said last named chain winding means in an unwinding direction.

8. ln a hand brake; the combination with an operating element; ot a tensioning member operatively associated with the brake rigging proper; means interposed between said operating; element and tensioning member for multiplying the leverage ratio, said means automatically changing trom a lower power leverage ratio to a higher power leverage ratio when a predetermined tension is reached; and automatically operable means for compensating` `tor increases in slack to thereby maintain a substantially constant amount ot slack in the brake mechanism.

9. ln a hand brake; the combination with a brake staff of winding drums mounted to rotate upon independent axes; a driving connection between said staff and one of said drums; a releasable clutch connection between the other of said drums and said stati, said clutch connection being` adapted to be rendered ineffective to rotate said last named drum upon a predetermined resistance being encountered during the chain winding operation; and means for limiting the unwinding rotation of said last named drum, said means being movable to adjusted positions to compensate tor increased slack in the brake chain.

l0. In a hand brake, the combination with a rotatable chain winding drum; ot means for rotating said drum to wind the chain thereon; means for limiting the unwinding rotation of said drum, said means being automatically advanced by the movement ot' said drum so as to compensate tor increased slack in the brake chain.

In witness that claim the foregoing I have hereunto subscribed my name this 25th day of October 1922.

JOHN F. OCONNOR. 

